[Inter-rater reliability while using the Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS) in patients with...

We examined the inter-rater reliability for the evaluation of patients with cervical dystonia by using the Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS) (translated into Japanese). The TWSTRS is a rating scale that assesses patients with cervical dystonia by grading their symptoms on a subscale of severity, disability, and pain. This study used to TWSTRS-severity scores to examine the inter-rater reliability among 27 evaluators (neurologists) by using videotaped images of 2 patients. Along with the total-severity score on the TWSTRS, the intra-class correlation (ICC) and the lower limit of the 95% confidence interval were calculated as indices of inter-rater reliability. A high ICC of 0.745 was obtained. The ICC obtained from another study conducted outside Japan was 0.763, which is almost equivalent to the result of our study. Thus, the TWSTRS has a favorable inter-rater reliability which suggests that this scale was sufficiently reliable to be used as an accurate and easily available rating tool during the treatment of cervical dystonia.